jsx-filename-extension.js

/**
 * @fileoverview Restrict file extensions that may contain JSX
 * @author Joe Lencioni
 */

'use strict';

// ------------------------------------------------------------------------------
// Requirements
// ------------------------------------------------------------------------------

const RuleTester = require('eslint').RuleTester;
const rule = require('../../../lib/rules/jsx-filename-extension');

const parsers = require('../../helpers/parsers');

const parserOptions = {
  ecmaVersion: 2018,
  sourceType: 'module',
  ecmaFeatures: {
    jsx: true
  }
};

// ------------------------------------------------------------------------------
// Code Snippets
// ------------------------------------------------------------------------------

const withJSXElement = 'module.exports = function MyComponent() { return <div>\n<div />\n</div>; }';
const withJSXFragment = 'module.exports = function MyComponent() { return <>\n</>; }';
const withoutJSX = 'module.exports = {}';

// ------------------------------------------------------------------------------
// Tests
// ------------------------------------------------------------------------------

const ruleTester = new RuleTester({parserOptions});
ruleTester.run('jsx-filename-extension', rule, {

  valid: [
    {
      filename: '<text>',
      code: withJSXElement
    },
    {
      filename: 'MyComponent.jsx',
      code: withJSXElement
    }, {
      filename: 'MyComponent.js',
      code: withoutJSX,
      options: [{allow: 'as-needed'}]
    }, {
      filename: 'MyComponent.jsx',
      code: withJSXElement,
      options: [{allow: 'as-needed'}]
    }, {
      filename: 'MyComponent.js',
      options: [{extensions: ['.js', '.jsx']}],
      code: withJSXElement
    }, {
      filename: 'notAComponent.js',
      code: withoutJSX
    }, {
      filename: '<text>',
      code: withJSXFragment,
      parser: parsers.BABEL_ESLINT
    },
    {
      filename: 'MyComponent.jsx',
      code: withJSXFragment,
      parser: parsers.BABEL_ESLINT
    }, {
      filename: 'MyComponent.js',
      options: [{extensions: ['.js', '.jsx']}],
      code: withJSXFragment,
      parser: parsers.BABEL_ESLINT
    }
  ],

  invalid: [
    {
      filename: 'MyComponent.js',
      code: withJSXElement,
      errors: [{message: 'JSX not allowed in files with extension \'.js\''}]
    }, {
      filename: 'MyComponent.jsx',
      code: withoutJSX,
      options: [{allow: 'as-needed'}],
      errors: [{message: 'Only files containing JSX may use the extension \'.jsx\''}]
    }, {
      filename: 'MyComponent.jsx',
      code: withJSXElement,
      options: [{extensions: ['.js']}],
      errors: [{message: 'JSX not allowed in files with extension \'.jsx\''}]
    }, {
      filename: 'MyComponent.js',
      code: withJSXFragment,
      parser: parsers.BABEL_ESLINT,
      errors: [{message: 'JSX not allowed in files with extension \'.js\''}]
    }, {
      filename: 'MyComponent.jsx',
      code: withJSXFragment,
      parser: parsers.BABEL_ESLINT,
      options: [{extensions: ['.js']}],
      errors: [{message: 'JSX not allowed in files with extension \'.jsx\''}]
    }
  ]

});